diff --git a/src/calng/CalibrationManager.py b/src/calng/CalibrationManager.py
index 39ae148256b152f7115b20dca11dbade6c34f982..7fc7cd61dceb10ad09ca8d952053a609f9818d4f 100644
--- a/src/calng/CalibrationManager.py
+++ b/src/calng/CalibrationManager.py
@@ -611,22 +611,15 @@ class CalibrationManager(DeviceClientBase, Device):
             if path not in managed_paths:
                 del managed_hash[path]
 
-        # Check for current values of managed keys on DAQ devices and
-        # update schema correspondingly.
-        if self._daq_device_ids:
-            daq_vals = await self._get_shared_keys(
-                self._daq_device_ids, ManagedKeysNode.DAQ_KEYS.keys())
-
-            for orig_key, managed_key in ManagedKeysNode.DAQ_KEYS.items():
-                managed_hash[managed_key, 'defaultValue'] = daq_vals[orig_key]
-
-        # Check for current values of managed keys on correction
-        # devices and update schema correspondingly.
-        corr_vals = await self._get_shared_keys(
+        # Retrieve any previous values already on running devices in
+        # order to update the defaultValue attribute in the schema just
+        # before injection.
+        prev_vals = await self._get_shared_keys(
             self._correction_device_ids, managed_keys)
 
-        for key, value in corr_vals.items():
-            managed_hash[key, 'defaultValue'] = value
+        if self._daq_device_ids:
+            prev_vals.update(await self._get_shared_keys(
+                self._daq_device_ids, ManagedKeysNode.DAQ_KEYS.keys()))
 
         # Retrieve the attributes on the current managed node. The
         # original implementation of toSchemaAndAttrs in the Node's
@@ -695,6 +688,12 @@ class CalibrationManager(DeviceClientBase, Device):
                     descr.accessMode = AccessMode.RECONFIGURABLE
                     descr.allowedStates = [State.ACTIVE]
 
+                    try:
+                        # If there's been a previous value before
+                        # injection, use it.
+                        descr.defaultValue = prev_vals[full_key]
+                    except KeyError:
+                        pass
                 else:
                     self.logger.warn(f'Encountered unknown descriptor type '
                                      f'{type(descr)}')